I've said this before so many times on the basis that anything remotely obvious as a prime is outrageously expensive, but this one is in my niche: brandability. That's all I am buying at the moment: Brandable domains that currently have no real intrinsic value but just might come up on someone's wish list. I'd definitely hold on to it.
Just out of interest, I regged aZooZa.com way back and had it snapped up for $600 - I had quite a few a?oo?a palindromes but they are all sold. Palindromes are great brand domains also if you can get them short enough and pronounceable.